validate_dbc

Github Action for validating .dbc files using cantools

A GitHub Action that lints CAN .dbc files for syntax and structural defects using cantools. Inspired by DBC Utility's DBC validation release checklist, it runs the checks that can be done without a live CAN bus. This should at the very least provide a lint.

Findings are emitted as GitHub Actions annotations, so they show up inline on the pull request. Errors fail the job, and warnings are reported but do not result in failure.

What it checks

Check	Severity
File does not parse in cantools (syntax / format error)	error
Signal overlap, out-of-bounds signal, or multiplexer error	error
Classical CAN message with payload length above 8 bytes	error
Duplicate signal name within a single message	error
Duplicate frame ids across messages (may be variant-specific)	warning
Standard id above 11 bits not marked extended	warning
CAN FD message with a non-standard payload length	warning
Physical min/max that cannot fit the signal's bit width and scale	warning

Out of scope (needs a real bus, captured logs, or human review, so it is deliberately not checked): log replay, physical-value plausibility, unit correctness, enum-vs-firmware agreement, and release-note review.

Usage

name: DBC Lint
on:
  pull_request:
    paths: ['**.dbc']
jobs:
  validate:
    runs-on: ubuntu-latest
    steps:
      - uses: actions/checkout@v4
      - uses: polymathrobotics/validate_dbc@v0.1
        # No inputs needed: validates every .dbc in the repo by default.

Validate only a single directory:

      - uses: polymathrobotics/validate_dbc@v0.1
        with:
          path: dbc_dir

Validate an explicit set of files:

      - uses: polymathrobotics/validate_dbc@v0.1
        with:
          files: |
            path/to/example.dbc

Inputs

Input	Default	Description
path	.	Directory searched recursively for .dbc files when files is empty.
files	''	Explicit space/newline-separated list of .dbc files. Overrides path.
python-version	3.10	Python version used to run the validator.
cantools-version	>=40,<41	Version specifier appended to cantools for pip install.

Versioning

Pin to a version tag (@v0.1) to receive compatible updates, or to a full commit SHA for maximum reproducibility.

License

Apache-2.0 — see LICENSE.